CGC card grading: the scale and its two 10s

CGC grading is the card grading service of CGC Cards (Certified Guaranty Company), which authenticates a card, grades it on a 1-10 scale with half points and seals it in a holder with a certification label. CGC Cards shares its ownership with CGC's comic book grading service.

The part that trips people up is the top. CGC has two 10s: Pristine 10, for a card CGC calls flawless under 10-times magnification, which gets a special gold label, and Gem Mint 10, a 10 that misses one Pristine requirement. Below them sits Mint+ 9.5.

Before you buy one

• Read which 10 it is. "CGC 10" in a title can mean either one. Read the label in the photo before you treat a slab as a Pristine 10.

• Watch for older labels. CGC's legacy key says a "CGC Trading Cards Gem Mint 9.5" or "CSG Gem Mint 9.5" equals today's Gem Mint 10, so an older 9.5 slab isn't today's Mint+ 9.5. Read the label's exact wording before you compare it with newer slabs.

• Compare CGC with CGC. Line a CGC grade up only with the same grade from CGC, not with PSA or BGS. The grader comparison shows how the 10s differ.

• Look up the cert number on CGC's site, where CGC shows images of the graded card, and compare them with the listing photos.

• Read the number, then the words. Sellers write "CGC 10", "CGC Pristine 10", "CGC Gem Mint 10", "CGC 9.5" and "CGC 9.0". The same 10 can be two different grades, while 9 and 9.0 are the same one, so check the label against the title.

A ChaseBoard CGC 10 watch takes both Pristine 10 and Gem Mint 10 titles, so read the label before you buy. A CGC 9 watch takes "CGC 9" and "CGC 9.0" but never "CGC 9.5".